use default settings for Black

16 files changed, 179 insertions, 179 deletions

diff --git a/vk/api.py b/vk/api.py
index 84efd91..b3f2a49 100644
--- a/vk/api.py
+++ b/vk/api.py
@@ -49,29 +49,29 @@ def _build_url(scheme, host, path, params=None, empty_params=False):
     else:
         raise TypeError()
     path = urllib.parse.quote(path)
-    return urllib.parse.urlunsplit((scheme, host, path, params, ''))
+    return urllib.parse.urlunsplit((scheme, host, path, params, ""))
 
 
 def _join_param_values(values):
     if isinstance(values, str):
         return values
     if isinstance(values, Iterable):
-        return ','.join(map(str, values))
+        return ",".join(map(str, values))
     return values
 
 
 def _join_path(base, url):
-    if not base.endswith('/'):
-        base += '/'
+    if not base.endswith("/"):
+        base += "/"
     return urllib.parse.urljoin(base, url)
 
 
-ACCESS_TOKEN = '9722cef09722cef09722cef071974b8cbe997229722cef0cbabfd816916af6c7bd37006'
+ACCESS_TOKEN = "9722cef09722cef09722cef071974b8cbe997229722cef0cbabfd816916af6c7bd37006"
 
 
 class Version(Enum):
     # https://dev.vk.com/en/reference/versions
-    V5_199 = '5.199'
+    V5_199 = "5.199"
     DEFAULT = V5_199
 
     def __str__(self):
@@ -79,7 +79,7 @@ class Version(Enum):
 
 
 class Language(Enum):
-    EN = 'en'
+    EN = "en"
     DEFAULT = EN
 
     def __str__(self):
@@ -87,24 +87,24 @@ class Language(Enum):
 
 
 class Method(Enum):
-    USERS_GET = 'users.get'
-    FRIENDS_GET = 'friends.get'
+    USERS_GET = "users.get"
+    FRIENDS_GET = "friends.get"
 
     def __str__(self):
         return self.value
 
 
 class CommonParameters(Enum):
-    ACCESS_TOKEN = 'access_token'
-    VERSION = 'v'
-    LANGUAGE = 'lang'
+    ACCESS_TOKEN = "access_token"
+    VERSION = "v"
+    LANGUAGE = "lang"
 
     def __str__(self):
         return self.value
 
 
 class API:
-    _ROOT_URL = 'https://api.vk.com/method/'
+    _ROOT_URL = "https://api.vk.com/method/"
 
     _SCHEME, _HOST, _ROOT_PATH = _split_url(_ROOT_URL)
 
@@ -127,9 +127,9 @@ class API:
             with urlopen(url) as response:
                 response = json.loads(response.read().decode())
                 # print(response)
-                if 'response' not in response:
+                if "response" not in response:
                     raise vk.error.InvalidAPIResponseError(response)
-                return response['response']
+                return response["response"]
         except (ConnectionError, URLError) as e:
             raise vk.error.APIConnectionError(str(e)) from e
 
@@ -154,6 +154,6 @@ class API:
         response = self._call_method(
             Method.FRIENDS_GET, user_id=user_id, fields=_join_param_values(fields)
         )
-        if 'items' not in response:
+        if "items" not in response:
             raise vk.error.InvalidAPIResponseError(response)
-        return self._filter_response_with_users(response['items'], deactivated_users)
+        return self._filter_response_with_users(response["items"], deactivated_users)
diff --git a/vk/last_seen.py b/vk/last_seen.py
index e5584eb..78d10b5 100644
--- a/vk/last_seen.py
+++ b/vk/last_seen.py
@@ -31,8 +31,8 @@ def _parse_platform(x):
 
 
 class LastSeenField(Enum):
-    TIME = 'time'
-    PLATFORM = 'platform'
+    TIME = "time"
+    PLATFORM = "platform"
 
     def __str__(self):
         return self.value
diff --git a/vk/mutuals.py b/vk/mutuals.py
index 3498632..9b687c2 100644
--- a/vk/mutuals.py
+++ b/vk/mutuals.py
@@ -57,8 +57,8 @@ class OutputSinkJSON(OutputSinkMutualFriends):
 
 
 class OutputFormat(Enum):
-    CSV = 'csv'
-    JSON = 'json'
+    CSV = "csv"
+    JSON = "json"
 
     def __str__(self):
         return self.value
@@ -72,14 +72,14 @@ class OutputFormat(Enum):
             return OutputSinkCSV(fd)
         if self is OutputFormat.JSON:
             return OutputSinkJSON(fd)
-        raise NotImplementedError(f'unsupported output format: {self}')
+        raise NotImplementedError(f"unsupported output format: {self}")
 
 
 def _parse_output_format(s):
     try:
         return OutputFormat(s)
     except ValueError:
-        raise argparse.ArgumentTypeError(f'invalid output format: {s}')
+        raise argparse.ArgumentTypeError(f"invalid output format: {s}")
 
 
 def _parse_args(args=None):
@@ -87,29 +87,29 @@ def _parse_args(args=None):
         args = sys.argv[1:]
 
     parser = argparse.ArgumentParser(
-        description='Learn who your ex and her new boyfriend are both friends with.'
+        description="Learn who your ex and her new boyfriend are both friends with."
     )
 
     vk.version.add_to_arg_parser(parser)
 
     parser.add_argument(
-        'uids', metavar='UID', nargs='+', help='user IDs or "screen names"'
+        "uids", metavar="UID", nargs="+", help='user IDs or "screen names"'
     )
     parser.add_argument(
-        '-f',
-        '--format',
-        dest='out_fmt',
+        "-f",
+        "--format",
+        dest="out_fmt",
         type=_parse_output_format,
         default=OutputFormat.CSV,
         choices=OutputFormat,
-        help='specify output format',
+        help="specify output format",
     )
     parser.add_argument(
-        '-o',
-        '--output',
-        metavar='PATH',
-        dest='out_path',
-        help='set output file path (standard output by default)',
+        "-o",
+        "--output",
+        metavar="PATH",
+        dest="out_path",
+        help="set output file path (standard output by default)",
     )
 
     return parser.parse_args(args)
@@ -132,5 +132,5 @@ def main(args=None):
     write_mutual_friends(**vars(_parse_args(args)))
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()
diff --git a/vk/platform.py b/vk/platform.py
index 7e22911..c7129e3 100644
--- a/vk/platform.py
+++ b/vk/platform.py
@@ -25,15 +25,15 @@ class Platform(Enum):
 
     @property
     def descr(self):
-        return f'the {_PLATFORM_DESCRIPTIONS[self]}'
+        return f"the {_PLATFORM_DESCRIPTIONS[self]}"
 
 
 _PLATFORM_DESCRIPTIONS = {
     Platform.MOBILE: '"mobile" web version (or an unrecognized mobile app)',
-    Platform.IPHONE: 'official iPhone app',
-    Platform.IPAD: 'official iPad app',
-    Platform.ANDROID: 'official Android app',
-    Platform.WINDOWS_PHONE: 'official Windows Phone app',
-    Platform.WINDOWS10: 'official Windows 10 app',
-    Platform.WEB: 'web version (or an unrecognized app)',
+    Platform.IPHONE: "official iPhone app",
+    Platform.IPAD: "official iPad app",
+    Platform.ANDROID: "official Android app",
+    Platform.WINDOWS_PHONE: "official Windows Phone app",
+    Platform.WINDOWS10: "official Windows 10 app",
+    Platform.WEB: "web version (or an unrecognized app)",
 }
diff --git a/vk/tracking/__init__.py b/vk/tracking/__init__.py
index d0809e7..76bc1b4 100644
--- a/vk/tracking/__init__.py
+++ b/vk/tracking/__init__.py
@@ -3,6 +3,6 @@
 # See LICENSE.txt for details.
 
 __all__ = (
-    'sessions',
-    'status',
+    "sessions",
+    "status",
 )
diff --git a/vk/tracking/db/__init__.py b/vk/tracking/db/__init__.py
index 51b1a7c..7095cf3 100644
--- a/vk/tracking/db/__init__.py
+++ b/vk/tracking/db/__init__.py
@@ -5,4 +5,4 @@
 
 from .format import Format
 
-__all__ = ('format',)
+__all__ = ("format",)
diff --git a/vk/tracking/db/backend/__init__.py b/vk/tracking/db/backend/__init__.py
index 0d3153f..8a1a7d7 100644
--- a/vk/tracking/db/backend/__init__.py
+++ b/vk/tracking/db/backend/__init__.py
@@ -6,7 +6,7 @@
 from . import csv, log, null
 
 __all__ = (
-    'csv',
-    'log',
-    'null',
+    "csv",
+    "log",
+    "null",
 )
diff --git a/vk/tracking/db/backend/log.py b/vk/tracking/db/backend/log.py
index 0ffee5c..6f3ebaa 100644
--- a/vk/tracking/db/backend/log.py
+++ b/vk/tracking/db/backend/log.py
@@ -15,7 +15,7 @@ class Writer(meta.Writer):
         handler = logging.StreamHandler(fd)
         handler.setFormatter(
             logging.Formatter(
-                fmt='[%(asctime)s] %(message)s', datefmt='%Y-%m-%d %H:%M:%S%z'
+                fmt="[%(asctime)s] %(message)s", datefmt="%Y-%m-%d %H:%M:%S%z"
             )
         )
         self._logger.addHandler(handler)
@@ -71,24 +71,24 @@ class Writer(meta.Writer):
 
     @staticmethod
     def _format_user_is_online(user):
-        return f'{user.full_name} is ONLINE.'
+        return f"{user.full_name} is ONLINE."
 
     @staticmethod
     def _format_user_is_offline(user):
-        return f'{user.full_name} is OFFLINE.'
+        return f"{user.full_name} is OFFLINE."
 
     @staticmethod
     def _format_user_last_seen(user):
-        return f'{user.full_name} was last seen at {user.last_seen.time_local} using {user.last_seen.platform.descr}.'
+        return f"{user.full_name} was last seen at {user.last_seen.time_local} using {user.last_seen.platform.descr}."
 
     @staticmethod
     def _format_user_went_online(user):
-        return f'{user.full_name} went ONLINE.'
+        return f"{user.full_name} went ONLINE."
 
     @staticmethod
     def _format_user_went_offline(user):
-        return f'{user.full_name} went OFFLINE.'
+        return f"{user.full_name} went OFFLINE."
 
     @staticmethod
     def _format_another_connection_error(e):
-        return f'Encountered a connection error which looks like the previous one: {e}'
+        return f"Encountered a connection error which looks like the previous one: {e}"
diff --git a/vk/tracking/db/format.py b/vk/tracking/db/format.py
index 5c88cb7..66d9132 100644
--- a/vk/tracking/db/format.py
+++ b/vk/tracking/db/format.py
@@ -12,9 +12,9 @@ from . import backend
 
 
 class Format(Enum):
-    CSV = 'csv'
-    LOG = 'log'
-    NULL = 'null'
+    CSV = "csv"
+    LOG = "log"
+    NULL = "null"
 
     def __str__(self):
         return self.value
@@ -26,7 +26,7 @@ class Format(Enum):
             return backend.log.Writer(fd)
         if self is Format.NULL:
             return backend.null.Writer()
-        raise NotImplementedError(f'unsupported database format: {self}')
+        raise NotImplementedError(f"unsupported database format: {self}")
 
     def open_output_file(self, path=None):
         if self is Format.CSV:
@@ -35,30 +35,30 @@ class Format(Enum):
             return self._open_output_log_file(path)
         if self is Format.NULL:
             return self._open_output_database_file(None)
-        raise NotImplementedError('unsupported database format: ' + str(self))
+        raise NotImplementedError("unsupported database format: " + str(self))
 
     @staticmethod
     def _open_output_log_file(path):
-        return io.open_output_text_file(path, mode='a')
+        return io.open_output_text_file(path, mode="a")
 
     @staticmethod
     def _open_output_database_file(path):
-        return io.open_output_text_file(path, mode='x')
+        return io.open_output_text_file(path, mode="x")
 
     def create_reader(self, fd=sys.stdin):
         if self is Format.CSV:
             return backend.csv.Reader(fd)
         if self is Format.LOG:
-            return NotImplementedError('cannot read from a log file')
+            return NotImplementedError("cannot read from a log file")
         if self is Format.NULL:
             return backend.null.Reader()
-        raise NotImplementedError('unsupported database format: ' + str(self))
+        raise NotImplementedError("unsupported database format: " + str(self))
 
     def open_input_file(self, path=None):
         if self is Format.CSV:
             return io.open_input_text_file(path)
         if self is Format.LOG:
-            raise NotImplementedError('cannot read from a log file')
+            raise NotImplementedError("cannot read from a log file")
         if self is Format.NULL:
             return io.open_input_text_file(None)
-        raise NotImplementedError('unsupported database format: ' + str(self))
+        raise NotImplementedError("unsupported database format: " + str(self))
diff --git a/vk/tracking/db/timestamp.py b/vk/tracking/db/timestamp.py
index 4a3892f..c9ed293 100644
--- a/vk/tracking/db/timestamp.py
+++ b/vk/tracking/db/timestamp.py
@@ -30,7 +30,7 @@ class Timestamp:
 
     @staticmethod
     def from_string(s):
-        return Timestamp(datetime.strptime(s, '%Y-%m-%dT%H:%M:%SZ'))
+        return Timestamp(datetime.strptime(s, "%Y-%m-%dT%H:%M:%SZ"))
 
     def __str__(self):
-        return f'{self.dt.isoformat()}Z'
+        return f"{self.dt.isoformat()}Z"
diff --git a/vk/tracking/sessions.py b/vk/tracking/sessions.py
index 5d545f1..843977d 100644
--- a/vk/tracking/sessions.py
+++ b/vk/tracking/sessions.py
@@ -144,10 +144,10 @@ class OnlineSessionEnumerator(MutableMapping):
 
 
 class GroupBy(Enum):
-    USER = 'user'
-    DATE = 'date'
-    WEEKDAY = 'weekday'
-    HOUR = 'hour'
+    USER = "user"
+    DATE = "date"
+    WEEKDAY = "weekday"
+    HOUR = "hour"
 
     def __str__(self):
         return self.value
@@ -162,7 +162,7 @@ class GroupBy(Enum):
             return online_streaks.group_by_weekday(db_reader)
         if self is GroupBy.HOUR:
             return online_streaks.group_by_hour(db_reader)
-        raise NotImplementedError(f'unsupported grouping: {self}')
+        raise NotImplementedError(f"unsupported grouping: {self}")
 
 
 _OUTPUT_USER_FIELDS = (
@@ -211,7 +211,7 @@ class OutputSinkCSV(OutputSinkOnlineSessions):
     @staticmethod
     def _key_to_row(group_by, key):
         if group_by not in OutputSinkCSV._CONVERT_KEY:
-            raise NotImplementedError(f'unsupported grouping: {group_by}')
+            raise NotImplementedError(f"unsupported grouping: {group_by}")
         return OutputSinkCSV._CONVERT_KEY[group_by](key)
 
     def process_database(self, group_by, db_reader, time_from=None, time_to=None):
@@ -222,9 +222,9 @@ class OutputSinkCSV(OutputSinkOnlineSessions):
 
 
 class OutputConverterJSON:
-    _DATE_FIELD = 'date'
-    _WEEKDAY_FIELD = 'weekday'
-    _HOUR_FIELD = 'hour'
+    _DATE_FIELD = "date"
+    _WEEKDAY_FIELD = "weekday"
+    _HOUR_FIELD = "hour"
 
     assert _DATE_FIELD not in map(str, _OUTPUT_USER_FIELDS)
     assert _WEEKDAY_FIELD not in map(str, _OUTPUT_USER_FIELDS)
@@ -260,7 +260,7 @@ class OutputSinkJSON(OutputSinkOnlineSessions):
     def __init__(self, fd=sys.stdout):
         self._writer = io.FileWriterJSON(fd)
 
-    _DURATION_FIELD = 'duration'
+    _DURATION_FIELD = "duration"
 
     assert _DURATION_FIELD not in map(str, _OUTPUT_USER_FIELDS)
 
@@ -274,7 +274,7 @@ class OutputSinkJSON(OutputSinkOnlineSessions):
     @staticmethod
     def _key_to_object(group_by, key):
         if group_by not in OutputSinkJSON._CONVERT_KEY:
-            raise NotImplementedError(f'unsupported grouping: {group_by}')
+            raise NotImplementedError(f"unsupported grouping: {group_by}")
         return OutputSinkJSON._CONVERT_KEY[group_by](key)
 
     def process_database(self, group_by, db_reader, time_from=None, time_to=None):
@@ -289,7 +289,7 @@ class OutputSinkJSON(OutputSinkOnlineSessions):
 class OutputConverterPlot:
     @staticmethod
     def convert_user(user):
-        return f'{user.first_name}\n{user.last_name}'
+        return f"{user.first_name}\n{user.last_name}"
 
     @staticmethod
     def convert_date(date):
@@ -301,14 +301,14 @@ class OutputConverterPlot:
 
     @staticmethod
     def convert_hour(hour):
-        return f'{hour}:00'
+        return f"{hour}:00"
 
 
 class OutputSinkPlot(OutputSinkOnlineSessions):
     def __init__(self, fd=sys.stdout):
         self._fd = fd
 
-    TITLE = 'How much time people spend online'
+    TITLE = "How much time people spend online"
 
     _FORMAT_KEY = {
         GroupBy.USER: OutputConverterPlot.convert_user,
@@ -320,7 +320,7 @@ class OutputSinkPlot(OutputSinkOnlineSessions):
     @staticmethod
     def _format_key(group_by, key):
         if group_by not in OutputSinkPlot._FORMAT_KEY:
-            raise NotImplementedError(f'unsupported grouping: {group_by}')
+            raise NotImplementedError(f"unsupported grouping: {group_by}")
         return OutputSinkPlot._FORMAT_KEY[group_by](key)
 
     @staticmethod
@@ -351,7 +351,7 @@ class OutputSinkPlot(OutputSinkOnlineSessions):
         bar_chart.enable_grid_for_values()
         bar_chart.only_integer_values()
         bar_chart.set_property(
-            bar_chart.get_values_labels(), fontsize='small', rotation=30
+            bar_chart.get_values_labels(), fontsize="small", rotation=30
         )
         bar_chart.set_value_label_formatter(self._format_duration)
 
@@ -374,9 +374,9 @@ class OutputSinkPlot(OutputSinkOnlineSessions):
 
 
 class OutputFormat(Enum):
-    CSV = 'csv'
-    JSON = 'json'
-    PLOT = 'plot'
+    CSV = "csv"
+    JSON = "json"
+    PLOT = "plot"
 
     def __str__(self):
         return self.value
@@ -388,7 +388,7 @@ class OutputFormat(Enum):
             return OutputSinkJSON(fd)
         if self is OutputFormat.PLOT:
             return OutputSinkPlot(fd)
-        raise NotImplementedError(f'unsupported output format: {self}')
+        raise NotImplementedError(f"unsupported output format: {self}")
 
     def open_file(self, path=None):
         if self is OutputFormat.PLOT:
@@ -407,17 +407,17 @@ def _parse_database_format(s):
     try:
         return DatabaseFormat(s)
     except ValueError:
-        raise argparse.ArgumentTypeError(f'invalid database format: {s}')
+        raise argparse.ArgumentTypeError(f"invalid database format: {s}")
 
 
 def _parse_output_format(s):
     try:
         return OutputFormat(s)
     except ValueError:
-        raise argparse.ArgumentTypeError(f'invalid output format: {s}')
+        raise argparse.ArgumentTypeError(f"invalid output format: {s}")
 
 
-_DATE_RANGE_LIMIT_FORMAT = '%Y-%m-%dT%H:%M:%SZ'
+_DATE_RANGE_LIMIT_FORMAT = "%Y-%m-%dT%H:%M:%SZ"
 
 
 def _parse_date_range_limit(s):
@@ -435,64 +435,64 @@ def _parse_args(args=None):
         args = sys.argv[1:]
 
     parser = argparse.ArgumentParser(
-        description='View/visualize the amount of time people spend online.'
+        description="View/visualize the amount of time people spend online."
     )
 
     vk.version.add_to_arg_parser(parser)
 
     parser.add_argument(
-        'db_path',
-        metavar='input',
-        nargs='?',
-        help='database file path (standard input by default)',
+        "db_path",
+        metavar="input",
+        nargs="?",
+        help="database file path (standard input by default)",
     )
     parser.add_argument(
-        'out_path',
-        metavar='output',
-        nargs='?',
-        help='output file path (standard output by default)',
+        "out_path",
+        metavar="output",
+        nargs="?",
+        help="output file path (standard output by default)",
     )
     parser.add_argument(
-        '-g',
-        '--group-by',
+        "-g",
+        "--group-by",
         type=_parse_group_by,
         choices=GroupBy,
         default=GroupBy.USER,
-        help='group online sessions by user/date/etc.',
+        help="group online sessions by user/date/etc.",
     )
     parser.add_argument(
-        '-i',
-        '--input-format',
-        dest='db_fmt',
+        "-i",
+        "--input-format",
+        dest="db_fmt",
         type=_parse_database_format,
         default=DatabaseFormat.CSV,
         choices=DatabaseFormat,
-        help='specify database format',
+        help="specify database format",
     )
     parser.add_argument(
-        '-o',
-        '--output-format',
-        dest='out_fmt',
+        "-o",
+        "--output-format",
+        dest="out_fmt",
         type=_parse_output_format,
         choices=OutputFormat,
         default=OutputFormat.CSV,
-        help='specify output format',
+        help="specify output format",
     )
     parser.add_argument(
-        '-a',
-        '--from',
-        dest='time_from',
+        "-a",
+        "--from",
+        dest="time_from",
         type=_parse_date_range_limit,
         default=None,
-        help='discard online activity prior to this moment',
+        help="discard online activity prior to this moment",
     )
     parser.add_argument(
-        '-b',
-        '--to',
-        dest='time_to',
+        "-b",
+        "--to",
+        dest="time_to",
         type=_parse_date_range_limit,
         default=None,
-        help='discard online activity after this moment',
+        help="discard online activity after this moment",
     )
 
     return parser.parse_args(args)
@@ -525,5 +525,5 @@ def main(args=None):
     process_online_sessions(**vars(_parse_args(args)))
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()
diff --git a/vk/tracking/status.py b/vk/tracking/status.py
index 7ef0b3c..8f1665e 100644
--- a/vk/tracking/status.py
+++ b/vk/tracking/status.py
@@ -155,9 +155,9 @@ def _parse_positive_integer(s):
     try:
         n = int(s)
     except ValueError:
-        raise argparse.ArgumentTypeError(f'must be a positive integer: {s}')
+        raise argparse.ArgumentTypeError(f"must be a positive integer: {s}")
     if n < 1:
-        raise argparse.ArgumentTypeError(f'must be a positive integer: {s}')
+        raise argparse.ArgumentTypeError(f"must be a positive integer: {s}")
     return n
 
 
@@ -165,52 +165,52 @@ def _parse_database_format(s):
     try:
         return DatabaseFormat(s)
     except ValueError:
-        raise argparse.ArgumentTypeError(f'invalid database format: {s}')
+        raise argparse.ArgumentTypeError(f"invalid database format: {s}")
 
 
 def _parse_args(args=None):
     if args is None:
         args = sys.argv[1:]
 
-    parser = argparse.ArgumentParser(description='Track when people go online/offline.')
+    parser = argparse.ArgumentParser(description="Track when people go online/offline.")
 
     vk.version.add_to_arg_parser(parser)
 
     parser.add_argument(
-        'uids', metavar='UID', nargs='+', help='user IDs or "screen names"'
+        "uids", metavar="UID", nargs="+", help='user IDs or "screen names"'
     )
     parser.add_argument(
-        '-t',
-        '--timeout',
-        metavar='SECONDS',
+        "-t",
+        "--timeout",
+        metavar="SECONDS",
         type=_parse_positive_integer,
         default=DEFAULT_TIMEOUT,
-        help='set refresh interval',
+        help="set refresh interval",
     )
     parser.add_argument(
-        '-O',
-        '--only-once',
-        action='store_true',
-        help='query the status only once and exit',
+        "-O",
+        "--only-once",
+        action="store_true",
+        help="query the status only once and exit",
     )
     parser.add_argument(
-        '-l',
-        '--log',
-        metavar='PATH',
-        dest='log_path',
-        help='set log file path (standard output by default)',
+        "-l",
+        "--log",
+        metavar="PATH",
+        dest="log_path",
+        help="set log file path (standard output by default)",
     )
     parser.add_argument(
-        '-f',
-        '--format',
-        dest='db_fmt',
+        "-f",
+        "--format",
+        dest="db_fmt",
         type=_parse_database_format,
         choices=DatabaseFormat,
         default=DEFAULT_DB_FORMAT,
-        help='specify database format',
+        help="specify database format",
     )
     parser.add_argument(
-        '-o', '--output', metavar='PATH', dest='db_path', help='set database file path'
+        "-o", "--output", metavar="PATH", dest="db_path", help="set database file path"
     )
 
     return parser.parse_args(args)
@@ -248,5 +248,5 @@ def main(args=None):
     track_status(**vars(_parse_args(args)))
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()
diff --git a/vk/user.py b/vk/user.py
index 60bde9f..62b24a5 100644
--- a/vk/user.py
+++ b/vk/user.py
@@ -37,23 +37,23 @@ def _parse_online_flag(x):
 
 
 class UserField(Enum):
-    UID = 'id'
-    FIRST_NAME = 'first_name'
-    LAST_NAME = 'last_name'
-    DEACTIVATED = 'deactivated'
-    HIDDEN = 'hidden'
+    UID = "id"
+    FIRST_NAME = "first_name"
+    LAST_NAME = "last_name"
+    DEACTIVATED = "deactivated"
+    HIDDEN = "hidden"
 
-    DOMAIN = 'domain'
-    ONLINE = 'online'
-    LAST_SEEN = 'last_seen'
+    DOMAIN = "domain"
+    ONLINE = "online"
+    LAST_SEEN = "last_seen"
 
     def __str__(self):
         return self.value
 
 
 class DeactivationReason(Enum):
-    DELETED = 'deleted'
-    BANNED = 'banned'
+    DELETED = "deleted"
+    BANNED = "banned"
 
     def __str__(self):
         return self.value
@@ -135,7 +135,7 @@ class User(Hashable, MutableMapping):
     def full_name(self):
         if not self.has_last_name:
             return self.first_name
-        return f'{self.first_name} {self.last_name}'
+        return f"{self.first_name} {self.last_name}"
 
     @property
     def is_deactivated(self):
diff --git a/vk/utils/bar_chart.py b/vk/utils/bar_chart.py
index 367a301..44fac3c 100644
--- a/vk/utils/bar_chart.py
+++ b/vk/utils/bar_chart.py
@@ -112,7 +112,7 @@ class BarChartBuilder:
 
         self._get_categories_axis().set_ticklabels(categories)
 
-        bars = self._ax.barh(bar_offsets, values, align='center', height=bar_height)
+        bars = self._ax.barh(bar_offsets, values, align="center", height=bar_height)
 
         if min(values) >= 0:
             self.set_values_axis_limits(start=0)
@@ -128,40 +128,40 @@ class BarChartBuilder:
         plt.show()
 
     def save(self, path):
-        self._fig.savefig(path, bbox_inches='tight')
+        self._fig.savefig(path, bbox_inches="tight")
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     import argparse
 
     parser = argparse.ArgumentParser()
 
-    parser.add_argument('--categories', nargs='*', metavar='LABEL', default=[])
-    parser.add_argument('--values', nargs='*', metavar='N', default=[], type=float)
+    parser.add_argument("--categories", nargs="*", metavar="LABEL", default=[])
+    parser.add_argument("--values", nargs="*", metavar="N", default=[], type=float)
 
-    parser.add_argument('--output', '-o', help='set output file path')
+    parser.add_argument("--output", "-o", help="set output file path")
 
     parser.add_argument(
-        '--align-middle',
-        action='store_true',
-        dest='labels_align_middle',
-        help='align labels to the middle of the bars',
+        "--align-middle",
+        action="store_true",
+        dest="labels_align_middle",
+        help="align labels to the middle of the bars",
     )
 
     parser.add_argument(
-        '--integer-values', action='store_true', dest='only_integer_values'
+        "--integer-values", action="store_true", dest="only_integer_values"
     )
     parser.add_argument(
-        '--any-values', action='store_false', dest='only_integer_values'
+        "--any-values", action="store_false", dest="only_integer_values"
     )
 
-    parser.add_argument('--grid-categories', action='store_true')
-    parser.add_argument('--grid-values', action='store_true')
+    parser.add_argument("--grid-categories", action="store_true")
+    parser.add_argument("--grid-values", action="store_true")
 
     args = parser.parse_args()
 
     if len(args.categories) < len(args.values):
-        parser.error('too many bar values')
+        parser.error("too many bar values")
     if len(args.categories) > len(args.values):
         args.values.extend([0.0] * (len(args.categories) - len(args.values)))
 
diff --git a/vk/utils/io.py b/vk/utils/io.py
index 7588cc0..d0f4271 100644
--- a/vk/utils/io.py
+++ b/vk/utils/io.py
@@ -15,7 +15,7 @@ class FileWriterJSON:
 
     def write(self, something):
         self._fd.write(json.dumps(something, indent=3, ensure_ascii=False))
-        self._fd.write('\n')
+        self._fd.write("\n")
 
 
 class FileReaderCSV:
@@ -29,7 +29,7 @@ class FileReaderCSV:
 class FileWriterCSV:
     def __init__(self, fd=sys.stdout, flush=False):
         self._fd = fd
-        self._writer = csv.writer(fd, lineterminator='\n')
+        self._writer = csv.writer(fd, lineterminator="\n")
         self._flush = flush
 
     @staticmethod
@@ -55,16 +55,16 @@ def _open_file(path=None, default=None, **kwargs):
             yield fd
 
 
-_DEFAULT_ENCODING = 'utf-8'
+_DEFAULT_ENCODING = "utf-8"
 
 
 def open_input_text_file(path=None):
-    return _open_file(path, default=sys.stdin, mode='r', encoding=_DEFAULT_ENCODING)
+    return _open_file(path, default=sys.stdin, mode="r", encoding=_DEFAULT_ENCODING)
 
 
-def open_output_text_file(path=None, mode='w'):
+def open_output_text_file(path=None, mode="w"):
     return _open_file(path, default=sys.stdout, mode=mode, encoding=_DEFAULT_ENCODING)
 
 
 def open_output_binary_file(path=None):
-    return _open_file(path, default=sys.stdout, mode='wb')
+    return _open_file(path, default=sys.stdout, mode="wb")
diff --git a/vk/version.py b/vk/version.py
index fc944ab..ecd6545 100644
--- a/vk/version.py
+++ b/vk/version.py
@@ -5,12 +5,12 @@ except ImportError:
 
 
 try:
-    __version__ = metadata.version('vk_scripts')
+    __version__ = metadata.version("vk_scripts")
 except Exception:
-    __version__ = 'unknown'
+    __version__ = "unknown"
 
 
 def add_to_arg_parser(parser):
     parser.add_argument(
-        '--version', '-V', action='version', version=f'%(prog)s {__version__}'
+        "--version", "-V", action="version", version=f"%(prog)s {__version__}"
     )